Biofeedback
The technique of making unconscious or involuntary bodily processes (as heartbeat or brain waves) perceptible to the senses (as by the use of an oscilloscope) in order to manipulate them by conscious mental control.

Barium
A chalky liquid used to coat the inside of organs so that they will show up on an x-ray.

Barium Enema X-Ray
See Lower GI Series.

Barium Meal
See Upper GI Series.

Barrett's Esophagus
Peptic ulcer of the lower esophagus. It is caused by the presence of cells that normally stay in the stomach lining.

Belching
Noisy release of gas from the stomach through the mouth. Also called burping.

Bernstein Test
A test to find out if heartburn is caused by acid in the esophagus. The test involves dripping a mild acid, similar to stomach acid, through a tube placed in the esophagus.

Bezoar
A ball of food, mucus, vegetable fiber, hair, or other material that cannot be digested in the stomach. Bezoars can cause blockage, ulcers, and bleeding.

Bile
Fluid made by the liver and stored in the gallbladder. Bile helps break down fats and gets rid of wastes in the body.

Bile Acids
Acids made by the liver that work with bile to break down fats.

Bile Ducts
Tubes that carry bile from the liver to the gallbladder for storage and to the small intestine for use in digestion.

Biliary Atresia
A condition present from birth in which the bile ducts inside or outside the liver do not have normal openings. Bile becomes trapped in the liver, causing jaundice and cirrhosis. Without surgery the condition may cause death.

Biliary Dyskinesia
See postcholecystectomy syndrome.

Biliary Stricture
A narrowing of the biliary tract from scar tissue. The scar tissue may result from injury, disease, pancreatitis, infection, or gallstones. See also Stricture.

Biliary System
See Biliary Tract.

Biliary Tract
The gallbladder and the bile ducts. Also called biliary system or biliary tree.

Bismuth Subsalicylate
A nonprescription medicine such as Pepto-Bismol. Used to treat diarrhea, heartburn, indigestion, and nausea. It is also part of the treatment for ulcers caused by the bacterium Helicobacter pylori (HELL-uh-koh-BAK-tur py-LOH-ree).

Bloating
Fullness or swelling in the abdomen that often occurs after meals.